Estimates of genetic parameters and phenotypic, genetic and environmental trends of some productive traits in Gyr cattle
Balieiro, E.S.; Pereira, J.C.C.; Valente, J.; Verneque, R.S.; Balieiro, J.C.C.; Ferreira, W.J.
Arquivo Brasileiro de Medicina Veterinaria e Zootecnia 52(3): 266-275
ISSN/ISBN: 0102-0935 Accession: 003435737
The aims of the present study were to estimate genetic parameters, and phenotypic, genetic and environmental trends for milk yield (MY), lactation length (LL), fat yield (FY) and fat content (FC) in Gyr dairy cattle, using multivariate derivative-free restricted maximum likelihood (MTDFREML) with an animal model and data from the Arquivo Zootecnico Nacional (Brazil), collected between 1962 and 1996.